33 research outputs found
Scalar-metric quantum cosmology with Chaplygin gas and perfect fluid
In this paper we consider the flat FRW cosmology with a scalar field coupled
with the metric along with generalized Chaplygin gas and perfect fluid
comprising the matter sector. We use the Schutz's formalism to deal with the
generalized Chaplygin gas sector. The full theory is then quantized canonically
using the Wheeler-DeWitt Hamiltonian formalism. We then solve the WD equation
with appropriate boundary conditions. Then by defining a proper completeness
relation for the self-adjointness of the WD equation we arrive at the wave
packet for the universe. It is observed that the peak in the probability
density gets affected due to both fluids in the matter sector, namely, the
Chaplygin gas and perfect fluid.Comment: 8 pages Late
Twisted Galilean symmetry and the Pauli principle at low energies
We show the twisted Galilean invariance of the noncommutative parameter, even
in presence of space-time noncommutativity. We then obtain the deformed algebra
of the Schr\"odinger field in configuration and momentum space by studying the
action of the twisted Galilean group on the non-relativistic limit of the
Klein-Gordon field. Using this deformed algebra we compute the two particle
correlation function to study the possible extent to which the previously
proposed violation of the Pauli principle may impact at low energies. It is
concluded that any possible effect is probably well beyond detection at current
energies.Comment: 16 pages Latex, 2 figures Some modifications made in the abstract,
introduction, typographical errors correcte
Dual families of non-commutative quantum systems
We demonstrate how a one parameter family of interacting non-commuting
Hamiltonians, which are physically equivalent, can be constructed in
non-commutative quantum mechanics. This construction is carried out exactly (to
all orders in the non-commutative parameter) and analytically in two dimensions
for a free particle and a harmonic oscillator moving in a constant magnetic
field. We discuss the significance of the Seiberg-Witten map in this context.
It is shown for the harmonic oscillator potential that an approximate duality,
valid in the low energy sector, can be constructed between the interacting
commutative and a non-interacting non-commutative Hamiltonian. This
approximation holds to order 1/B and is therefore valid in the case of strong
magnetic fields and weak Landau-level mixing.Comment: 11 pages, no figure
Central Bank Intervention in Foreign Exchange Market under Managed Float: A Three Regime Threshold VAR Analysis of Indian Rupee-US Dollar Exchange Rate
We try to comprehensively analyze the nuances of Central Bank’s intervention in the foreign exchange market under a managed float exchange rate regime. We employ a three regime threshold VAR model and identify two endogenously determined threshold values of exchange rate cycle beyond which the Reserve Bank of India (RBI) intervenes in the Indian Rupee–US Dollar (Re/ exchange rate within the desired band. Within the band, the RBI tries only to mitigate domestic inflationary conditions
Central Bank Intervention in Foreign Exchange Market under Managed Float: A Three Regime Threshold VAR Analysis of Indian Rupee-US Dollar Exchange Rate
We try to comprehensively analyze the nuances of Central Bank’s intervention in the foreign exchange market under a managed float exchange rate regime. We employ a three regime threshold VAR model and identify two endogenously determined threshold values of exchange rate cycle beyond which the Reserve Bank of India (RBI) intervenes in the Indian Rupee–US Dollar (Re/ exchange rate within the desired band. Within the band, the RBI tries only to mitigate domestic inflationary conditions
Lorentzian path integral in Kantowski-Sachs anisotropic cosmology
Motivated by the recent development in quantum cosmology, we revisit the
anisotropic Kantowski-Sachs model in the light of a Lorentzian path integral
formalism. Studies so far have considered the Euclidean method where the choice
of the lapse integration contour is constrained by certain physical
considerations rather than mathematical justification. In this paper, we have
studied the Hartle-Hawking no-boundary proposal along with the use of
Picard-Lefschetz theory in performing the lapse integration. In an isotropic
limit, we show our results agree with the studies made in FLRW cosmology. We
also observe that in the large scale structure the no-boundary proposal tends
towards a conical singularity at the beginning of time. We have also performed
a massless scalar perturbation analysis with no back reaction. This reveals
that if there were any perturbation present at the beginning of the universe
then that would flare up at the final boundary.Comment: 9 pages, 4 figure